Denture.



A. GYSI.

DENTURE. APPLICATION FILED MAR. 28, 1910.

990,548, Patented Apr. 25, 1911.

' scription their grinding function.

position in the soft wax plate.

Fig. 3 a back view,

neurons.

.Specification of Iietters Patent.

Patented Apr. 25, 1911.

Application filed March 28, 1910. Serial No. 552,080.

To all whom it may concern:

Be it known that I, ALFRED Grsr, a citizen of the Republic of Switzerland, residing at Obere Ztiune 10, Zurich, Switzerland, have invented certain new and useful Improvements in Dentures; and I do hereby declare the following to be a full,clear, and exact deof the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and'to letters or figures of reference marked thereon, which form a part of this specification.

The subject of the present invention is an improved form of artificial teeth, consisting of a block presenting the form of the crowns of four contiguous molars.

As is well known, each molar must occupy a certain position relatively both to the adjacent and the superposed molars, in order that the teeth may properly perform It is however, a difficult and tedious operation for the dentist to fix the individual molars in the correct By means of my invention this work is essentially facilitated.

A practical embodiment of my invention is illustrated in the accompanying drawings, in which' Figure 1 is a front elevation, Fig.2 a plan, and Fig. 4: an underside view of the denture. Fig. 5 is an elevation, showing an upper anda lower denture in their operative position. Fig. 6 is a section on the line AB of Fig. 1. Figs. 7 and 8 are two cross-sectional views through assembled upper and lower dentures, illustrating the mode of operation.

The denture consists of a block, for instance, of porcelain or other suitable material, which may be white, or of the color of the natural teeth. This block presents four sections 1, 2, 3, 4. The sections 3,4 are of shape of the crowns of adjacent reater molars (true molars) while the sections 1, 2 have the shape of the crowns of adjacent lesser molars (premolars). All four sections together constitute an integral, solid block, complete in itself, without any addition, such, for example, as red porcelain m. On the underside of the sections 1, 2 a longitudinal saddle groove 5 is provided;

while. onthe underside of the sections 3, 4; two such longitudinal grooves nished. These grooves prevent lateral slipping of the block when pressed upon the soft wax mass 8, 9 (Figs. 7 and 8) (3, 7 are fur- On the underside of each of the four sections 1, 2, 3, 4 there is provided also a transverse dovetailed groove 10. These grooves 10 do not run right across the sections, but terminate in a recess 11 (Fig. (3) shortly before reaching the front wall of the block. The grooves 10, therefore, are not'visible from the front of the block, that is to say from the side which lies nextthe check of the wearer of the denture (Fig. 1). The final caoutchouc mass enters these transverse grooves 10 with recess 11. so that the block can shift neither in the longitudinal nor vertical direction.

To prevent breaking of the block at the places of junct-ion'of two sections, its underside at such parts is furnished with strengthening-ribs 12. These ribs are particularly advantageous in cases in which, in consequence of deficiency of room, thin blocks have to be employed. The ribs 12 also enable a peculiarly firm joint to be made between block and caoutchouc.

The top of the block presents a deep angular main groove 12-3. which runs in longitudinal direction. This groove 13 divides each of the sections 3, 4 into two prominences. Of these latter, the one is sub-divided into two protuberances by a transverse groove 1%, while the other remains undivided and is of rounded shape.

When the upper and lower dentures are assembled, as shown in Figs. 7 and 8, there are but few points of contact between the superposed sections, or teeth, owing to the main grooves 13 being deep and angular. This holds good even when the teeth, instead of occupying the normal position as shown in Fig. 7, occupy a false position'the so called cross bite as depicted in Fig. 8. This latter position occurs when the natural teeth have been absent for agreat length of time, in which event the'upper jaw naturally becomes smaller and the lower jaw larger than normally.

The block is given a somewhat curved shape, depending upon whether it is to be used for the upper or lower jaw, as shown in Fig. 5. That block which is designed for the right position relatively to those of the upper -j aw. 'VVhen, however, the four molars: are all presented by an integral bl0ck,'and

are thus all permanently in their correct natural position, it is obviously much easier to insert the four molars correctly in the caoutchouc plate.

It has already been proposed to unite two,

or even three, molars with each other, so as to constitute a single block; but these have been so-called pinteeth and have, .moreover, been in connection with a red porcelain/piece. Furthermore the fourth molar has had to be inserted separately, and the manner of fastening, like the shape of the teeth, has, as alreadyremarked, been another. The method has also been tried of uniting four incisor teeth to form a block,

but red porcelain gum has been used in this case also, and the teeth have been arranged for metal. pin fastening. These four incisors instead of two pairs, are made to form a single block of united incisor teeth, so that the joint, in the porcelain gum is avoided.

- But the proposal has never been made of ascertained the nature of thesaid invention constructing a denture of ablock which presents the form of the crowns of four con- 'tlguous molars.

Having now particularly described and and in what manner the same is to be per formed, I declare that what I claim is 1. A denture, comprising a block presenting the form of the crowns of four contiguous molars,

the two foremost of the four crowns being provided on the underside those portionswhich represent nal saddle groove, substantially as described.

2. A denture, comprising a block presenting the form of the crowns of four contiguous molars, those portions which represent the two foremost of the four crowns being provided on the underside Wlthfl. longitudinal saddle groove, while the portions'which represent the two backmost of the four crowns are furnished on the underside with two such grooves, substantially as described.

3. A denture, comprising'a block presentwith a longitudi ing the form of the-crowns of four contiguous molars, the underside of'each of thefour portions which represents a crown being provided with a transverse dovetailed groove which terminates at one end in a recess, substantially as described.

4. A denture, comprising a block presentlng the form of the crowns of four contiguous molars, the underside of the parts Where each portion representing a crown is connecte with the adjacent portion being provided with a strengthening-rib, substantially as described.

A denture, comprising a block presenting the form of the crowns of four contiguous molars, and provided on the top with a deep angular longitudinal main groove,

while those portions ,which represent the crowns of the two backmost molars are provided on the one side of the said groove with a transverse channel. so that the said portions on the one side of the main groove present only a single prominence, and on the opposite side, two prominences, substantially as described. 1

In testimony that I claim the foregoing i as my invention, I have signed my name in presence of two subscribing witnesses.

. ALFRED GYSI. Witnesses:

' ERNST FISCHER,

. CA L GU'BLER. 

